The Abu Dhabi Department of Education and Knowledge (ADEK) says penalties for schools breaking the pandemic protocols range from AED 10,000 to 250,000.
Making the announcement on Saturday, ADEK added that parents will also be entitled to remove their children, with fee refunds for repeated non-compliance.
It says inspectors have conducted tests on 221 schools and 119 nurseries that have reopened for in-classroom lessons.
Repeated non-compliance can also lead to schools being forced to shift to distance learning provision.
Based on inspections, non-compliant nurseries can be moved immediately to distance learning for a week, or fined.
The checks track adherence across a range of 62 criteria, including maintaining social distancing protocols; on-premise COVID taskforces; regular cleaning and disinfection programmes; regular COVID-19 testing of staff and students aged 12 and above; regulated classroom numbers, PPE equipment standards, and daily routine checks conducted by a nominated school compliance officer to ensure safety regulations are being followed.
Amer Al Hammadi, Undersecretary of ADEK, hoped that "none of these penalties will have to be exacted".
"We have confidence in our school and nursery communities and their desire to adhere to the regulations for the safety of all," he added.
ADEK has also announced the ban on extracurricular activities on school premises will remain in force, with light athletic activities only allowed outdoors during normal scheduled PE classes and under social distancing rules.
In addition, parents will be allowed to enter school premises providing they show a negative PCR test result with 96-hour validity or demonstrate "emergency use" status on their Al Hosn App.
School tours for new and prospective parents are allowed to resume, while class sizes have been increased to a maximum of 30 students with 1.5 metre social distancing and compulsory face masks for Grade 1 and above.